Visual displays have advanced to the point where many are small, thin, nearly flat and light-weight. Visual displays include LED flat panel displays and LCD flat panel displays. Some video displays allow the user to identify images provided on the visual display by touching a surface covering the visual display, and these are commonly referred to as “touch-screen monitors”. A touch-screen monitor is commonly used to provide a user with an easy means to identify icons and otherwise control a computer without the use of a mouse. However, touch-screen monitors are not without problems.
For example, existing touch-screen monitors that are based on capacitance require use of a conductive object, such as a finger, carbon filled stylus, or metal stylus, and the conductive object must be grounded to the display's case. As such, these capacitance-based touch-screen monitors do not work well when water exists between the touch-screen monitor and the conductive object, such as when the monitor is wet from rain, or the object is a sweaty finger.
Other touch-screen monitors are optically-based. These optical-based touch-screen monitors may not work properly in direct sun light or in darkness because the optical sensors require some, but not too much, ambient light in order to function properly.